Generally speaking, the electronic equipment relies on the power module like adaptor or built-in power for converting the input voltage into the working voltage, therefore the working voltage can drive the electronic equipment. Take the conventional adaptor for example; the structure comprises the upper and lower housings to encapsulate the circuit board therein. The input voltage is converted into the working voltage by the electronic components such as capacitor, resistor, transformer, and diode on the circuit board of the power module for keeping the operation of the electronic equipment.
The voltage converting efficiency of the power module is getting higher with the increasing working efficiency of the electronic equipment; therefore a lot of heat is produced by those high power electronic components on the circuit board. For dissipating the heat produced by those high power electronic components, a certain space is designed in the housing or a heat sink is attached on those high power electronic components to dissipate heat by conduction, so as to avoid over-temperature shutdown of the electronic components.
With the requirement of the miniaturization, portability, high efficiency and stability of the electronic equipments, it is necessary to fabricate a miniaturized power module with high stability and low cost. However, to reduce the volume of the power module is not a simple task if a certain space has to be reserved in the housing or a heat sink is to be attached on the electronic component on the circuit board for dissipating heat.
Although the miniaturized power module to be plugged into the system circuit board of the electronic equipment directly for generating the working voltage has already been developed in the market, the heat is dissipated only by conducting to the system circuit board through the pins of the miniaturized power module plugged into the system circuit board or by convection or radiation through the housing. Moreover, more heat is produced by the high power electronic components in the miniaturized power module, so the heat cannot be dissipated efficiently from the housing and the accumulated heat may cause the shutdown of the electronic equipment.
Therefore, it is required to develop a power module fabrication method and the structure thereof to improve the heat dissipation of the miniaturized power module, simplify the fabrication method and lower the cost.